Fundamentos de Telecomunicações

Objectives

The subject aims at presenting the fundamental concepts in Telecommunications, namely the analog (AM, FM, PM) and the digital modulations (ASK, PSK, FSK e QAM), the input/output signal-to-noise ratios, the bandwidth, the symbol/bit error probabilities and the source and channel codings. Some mathematical tools, which are important to understanding Telecommunications, are also introduced, such as the spectrum of a deterministic signal, the power spectrum of a random signal and the channel capacity of a digital link.

Syllabus

I- Introduction to Telecommunications. Analog and digital systems. II- Basic concepts. Important signals. Fourier series. Fourier transforms. Response of linear systems. III- Random signals. Random variables. Stochastic processes. Stationarity and ergodicity. Power spectra. IV- Analog Communications. Amplitude modulations (AM) and angle modulations (FM, PM). Bandwidth. Receivers. V- Effect of noise on the analog communications. Bandpass noise. Signal-to-noise ratios. Modulation performance. VI- Baseband digital communications. Source coding. Shannon theorem. Sampling. PCM. Line codes. Correlation receiver. VII- Digital bandpass communications. Binary and M-ary modulations. Geometric representation of modulated signals. ASK, PSK, FSK and QAM modulations. ML receiver. VIII- Other topics in digital communications. Detection and error correction techniques (ARQ and FEC). Block codes. Link budget analysis.

Cross Competence Component

The subject includes 3 laboratory works where it is asked the team elements (typically 3 student/group) to build the reports. The writing of each report requires previous discussion of the topics to be presented.

Laboratorial Component

The laboratory component consists of three team experimental works and corresponding reports about topics presented in the class: amplitude modulation/demodulation (AM), frequency modulation/demodulation (FM) and binary PSK transmission/reception.

Ethical Principles

All members of a group are responsible for the group’s work In any assessment, every student shall honestly disclose any help received and sources used. In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.